How to repeat an image which uses Sphere mapping in Cycles
The problem is that the texture coordinates node is not outputting a UV coordinates it is a genereted 3D coordinates ranging from 0 to on each axis ( X,Y and Z ) and since the Sphere mapping is not linear like the cube , scaling these coordinates will not get the desired result.
instead of manipilating the 3D generated coordinates I extracted the UV coordinates from the sphere projection and used this as a UV coordinates for the real image which is mapped using Flat projection.
extracting the UV coordinates from the Sphere projection is done by two gradiant image texture ( black to white direction is the same as the U and V axis direction ) 

here is the node setup :



Now you can manipulate the texture mapping as you want :



Note : you can eliminate the need for two image texture nodes in the first stage by using one image with  red gradient ( horizontal) and a green gradient ( vertical ) in one image 

first image : used for U axis 



second image : used for the V axis